Supplementary
Completing or enhancing something.
Something additional; an extra.
Supplemental (adjective)
Acting to supplement.
Supplemental (adjective)
Appending.
Supplemental (adjective)
Lacking a regular schedule (as in a supplemental airline).
Supplemental (noun)
Something that supplements or adds to.
Supplemental (noun)
A requisition or article of legislation that provides additional funding for a program.
Supplementary (adjective)
Additional; added to supply what is wanted.
Supplementary (noun)
Something additional; an extra.
Supplemental (adjective)
provided in addition to what is already present or available to complete or enhance it
“many premature infants need supplemental oxygen soon after birth”
Supplementary (adjective)
completing or enhancing something
“the development of databases supplementary to existing ones”
“the programme offers supplementary information about the news”
Supplementary (noun)
a supplementary person or thing.
Supplementary (noun)
a question asked in parliament following the answer to a tabled one.